Adults 85 years and older (the oldest old), the majority of whom are women, comprise the fasting growing segment of the United States population. This rapidly expanding population of very elderly adults will strain a health care system already overburdened by rising costs. Identification of valid biologic and psychosocial markers of successful or optimal aging is needed to direct the design of future intervention studies aimed at targeting high risk individuals early on in the aging process and to inform public health initiatives aimed at promoting optimal aging. In this proposal, we propose to continue the Study of Osteoporotic Fractures (SOF) the largest and best characterized cohort of women in their 9th and 10th decade of life. SOF has become a national resource for studies of aging and SOF data have been increasingly utilized to advance understanding of the determinants of longevity including patterns of optimal aging. A total of 7280 women aged 65 years and older were originally enrolled in SOF at 3 clinical centers in 1986-87, with expansion of the cohort to 7760 with the enrollment of 480 African Americans in 1997-98. Of these, over 2300 have survived to at least age 90. Participants have attended up to 9 clinical examinations and completed tri-annual contacts (over 95% completed during 22 years of follow-up) providing a comprehensive powerful archive of measurements. We now propose to use the unique 20 years of repeated measurements in SOF to define age-related trajectories of cognitive function, physical performance, bone mineral density, body weight and positive affect. We will then use the newly established linkage of SOF data with Medicare claims data and continued follow-up of SOF participants to test whether these trajectories identify women who have attained the phenotype of optimal aging as defined by longevity, active lifespan (survival free of major disability), exceptional health span (survival free of major disease events), and lower rates of inpatient and residential health care utilization. The specific aims of our proposal are to: 1) Determine the association of age-related parameter trajectories with longevity and active lifespan in older women; 2) Determine the association of age-related parameter trajectories with exceptional health span in older women; 3) Determine the association of age-related parameter trajectories with inpatient and residential health care use as characterized by inpatient hospitalization days, rehabilitation days in inpatient facility, rehabilitation days in skilled nursing facility, and survival free of permanent placement in skilled nursing facility; and 4) Sustain and actively use the extensive SOF biologic repository of serum, urine and DNA specimens. Identification of trajectories predicting survival with improved functional, disease and health care outcomes and the data generated regarding the window prior to decline is a critical first step needed prior to the design of intervention studies aimed at targeting vulnerable older individuals at an earlier age.